<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .active {
            color: red;
        }
    </style>
</head>

<body>
    <div id="app"></div>

    <template id="my-app">
        <!-- 对象语法: { 'active': boolean } -->
        <h2 :class="{ 'active': isActive }">{{ message }}</h2>
        <button @click="isActive = !isActive">切换</button>
    </template>

    <script src="../js/vue.js"></script>

    <script>
        const App = {
            template: "#my-app",
            data() {
                return {
                    message: "Hello World",
                    isActive: true
                }
            },
            methods: {

            }
        }

        Vue.createApp(App).mount("#app");
    </script>
</body>

</html>